I had one in a mixed reef tank with a cleaner shrimp for a year or so. I had not fed the tank due to a week long vacation. When I returned and fed the fish the shrimp swam up to my hand to grab food and was quickly bit in half by the trigger. As crazy as it sounds, it seemed like the trigger realized his mistake and didn't finish eating the shrimp. I had soft corals only and it did not bother any. He did knock over or push around some smaller rocks and frags in his search for food.
I've always had blue throat triggers in my FOWLER and reef tanks. They are one of the most well behaved triggers in my opinion. They loved being cleaned by my cleaner shrimp and never nipped at them. Granted I had the cleaners in BEFORE the triggers, so the cleaners were well established. I never had a problem with them harming any of my coral either.
I've had Niger Triggers too. You have to be careful with them. Those can be a "luck of the draw" kind of trigger. I've seen some very docile ones at my local fish stores and others that are just down-right mean.